報告時間：2018年7月13日下午15:00-16:00

報告地點： X7503（代數(shù)編碼研討室）

主持人：周正春教授

Title: Improved adaptive belief-propagation (ABP) decoding for high-density parity check codes

Abstract: ABP decoding is a soft-decoding approach for high-density parity check codes such as BCH codes and Reed-Solomon (RS) codes. The main idea of conventional ABP decoder is to adaptively sparsify columns of parity-check matrix corresponding to the (n-k) least-reliable bits using Gaussian elimination (GE) followed by BP decoding in each iteration, wherenandkdenotes codeword length and message length, respectively. In this talk, I will introduce an improved ABP decoding method in which a small number of columns (say,p) corresponding to randomly selected reliable bits are selected in GE, in addition to columns associated ton-k-pleast-reliable bits. Mutual information analysis shows that this new decoding strategy is able to extract larger amount of extrinsic information and therefore leads to significantly improved decoding performance. As an application of this improved ABP decoding, I will present a series of numerical results for a BCH-coded continuous phase modulation (CPM) turbo receiver in which improved ABP brings in fast convergence and lower error floor in turbo decoding.

Bio: Dr Zilong Liu (https://sites.google.com/site/zilongliu2357) is a Senior Research Fellow in the 5G Innovation Centre, University of Surrey. From July 2008 to January 2018, he was with the School of Electrical and Electronic Engineering, Nanyang Technological University (NTU), Singapore, first as a Research Associate and since Nov. 2014 a Research Fellow. From Aug. 2009 to Aug. 2013, he was a PhD candidate (part-time) working on “Perfect- and Quasi- Complementary Sequences”, advised by Prof. Yong Liang Guan. He was a visiting Ph.D student in the University of Melbourne (UoM) from May 2012 to Feb. 2013 [hosted by Prof. Udaya Parampalli], and in the Hong Kong University of Science and Technology (HKUST) from June 2013 to July 2013 (hosted by Prof. Wai Ho Mow). He received his M.S. degree in the Department of Electronic Engineering from Tsinghua University and B.S. degree in the School of Electronics and Information Engineering from Huazhong University of Science and Technology (HUST), in 2007 and 2004, respectively. Dr. Liu is generally interested in coding and signal processing for various communication systems, with emphasis on algebraic coding and signal design, iterative receiver design, soft-decoding of error correcting codes, robust/efficient multiuser communications, and PHY implementation of communication systems.

劉子龍博士將在我院“代數(shù)編碼”團隊訪問1個星期，共同探討5G通信中的新型序列設計問題。